Boiler with forced return circulation through furnace walls



URNACE WALLS Oct. 18, 1932. D. s. JACOBUS BOILER vmn roncan'ma ruxu cmcumnou 'rnnouea F original Filed Oct. :51. 192'? 2 Sheets-Sheet 1 INVENTOR RTTORNEYS Oct. 18, 1932; v D. s; JACOBUS BOILER II 'I'H FORCED RETURN CIRCULATION THROUGH FURNACE WALLS Original Filed 001;. 31. 1927 2 Sheets-Sheet 2 J z 7/ INVENTOR AT ORNEYS' Patented Oct. 1a 19;: 7 1 3332 93 UNITED STATES PATENT orrics navm s. .mconus, or MON'ICLAIR, NEW JERSEY, AssIcNoN ro THE BABCOCK a wrLcox comm, or BAYONNE; NEW Jersey; A CORPORATION on NEW JERSEY L v 1 BOILER WITH FORCED RETURN CIRCULATION THRQUGB; FURNACE ;WAL1 28 I Application filed October 31, 1927, Serial No. 229,893, .Rencwed June 23, 1932.

This invention relates to a boiler that is arator 27. 'A tube 28 leads from the water provided with an *economizer and with space of the s'teamand water separator 25 means by which a portion of the feedwater toa pipe 29 that is connected to the water can be heated by blow-oil water and introspace of the steam'and water separator 27. s duced into the boiler without passing A pipe 30 leads from the steam space of the 55 through the economizer. Theinventlon will steam and water separator 27 to the superbe understood from the description in conheater 31.' Water. level indicators 32 are nection with the accompanying drawings in provided for the steam and water separators which Fig. 1 is a vertical section through an 25 and27. A float 33 is located in the steam 10 illustrative embodiment .of the invention and water separator 27 and controls the taken along the line 11 of Fig. 2; and valve-'34, in the feed water'line35. The feed Fig. 2 is a view partly in, section taken along water line 35 leads through the pipes36 and the line 2-2 'of Fig. 1." In the drawings 37 to the lower header 38 of an economizer of reference character 4 indicates the furnace which the lower or heating section is shown 15 of the boiler that has water tubes along its at 39. The lower or heating section 39 of g walls, roof and floor Fuel burners are the economizer is connected as shown at 40 shown at 5. The row of front wall tubes'is to the upper or steaming section 41 of the indicated. at 6, the side wall tubes at 7, the economizer and a tube 42 provided with a rear wall tubes at 8, and the roof tubes at 9. valve 42 leads from the upper section to the .9 A U-shaped lower headerlO is located at. steam and water separator 25. The lower the lower portion of the furnace and the sect1on39 and the upper section 41 ofthe tubes 6 are connected from the frpnt poreconomizer are spaced apartand the supertion of the header to the upper front heater 31 is located in this space.

, header 11. The rows of side wall tubes 7 The outlet'condujt 45 from the economizer 2 connect the legs of the U-shaped header 10 leads to an airheater 46 from which a con- 75 to upper headers 13 along the sides of the duit 47 leads to=the stack. Thecold' air inmate. The row of tubes '8 connects a let for the air heater 46' is shown at 48 and lower header 14 to an upper header and the hot air outlet is shown at 49, which may the row of roof tubes 9 connects the header lead to the combustion space of the furnace. I

so 11.to the header 16. 4 A heat exchanger 50 has a pipe 29 con- A row of tubes 18 connects the lower headnected thereto and is provided with a valved er 14 to the header 19. The tubes 18 are blow-ofi' 0r dra'inpipe51; -A branch 52 leads a bent so that 'an inclined portion of these from the feed pipe to a coil 53 iuside'of tubes lies along the floor of the furnace and the heat exchanger and a thermostatic 85. the remainder of the tubes lie along one side control 54of the same-general type as illus- 5- of an outlet passage for ashes. The front tratedin Patent 1,543,727 is provided in the side ofthe U-shaped header-10 is connected outlet from the coil 53. The outlet from the by a row of tubes 20 to a header 21 that is thermostatic control 54 leads to a pipe 55 located at the samedevel astheheader 19, that connects the pipe 29 to a circulating 10 the row of'tubes 20 forming one side of the ump 56. Thermometers 57 58 and 59 may at. outlet for ashes from the furnace. The rows I e,provided toindicate'the temperatures at of tubes may be lined with tile in the well the respective locations. The outlet 60 for own' manner. the pump 56 has branches that lead to the A pipe 22 rovided with a valve 22' leads headers 19 and 21. A' by-pass 62 provided Hi from the has. er 13 to 'a steam and water sepwith a valve 63 is provided between the feed I stator 25 and a pipe 23 providedwith a water pipe 36 to the economizer and the pipe valve 23' leads from'the header 15 to the 60, and a valve 64' is provided in the pipe 60 same separator; A steam pipe 26 leads from beyond the by-pass 62. 1 1 .the steam space of the steam and wa'ter'sep- The operation is as follows: Feedwater is o arator 25 to a econd 'steamand water sepintroduced through the pipe 35 and the we pipe 26 into the separator 27, and steam passes through thepipe from the separator 27 flto the superheater 31, and thence to the steam main. \Vater passes from the separaters 25 and '27 through the pipes 28 and 15 29 and is forced through the pipes andGO by means of the pump 56 through the headers and tubes around the furnace 4. The' 'lnixture of steam and water then passes through the pipes 22 and 23 to the separators 0 25 and the water is again circulated by means of the pump" 56.

I In order to prevent the water that is circulated through the furnace Wall tubes from becoming too concentrated with impurities,

some of this water may be continuously I claim: 1. The process which comprises posltively circulating water only through the steam generating tubes of a boiler during normal opleading to said economizer to permit said pump to circulate fluid through said econo-' mizer and through said boiler simultaneously.

3. The combination with a'forced circulation boiler of a pump for maintaining circulation'therethrough, an economizer connected to said boiler, mea ns'for feeding water to said economizer, and a valve controlled connection from the discharge of said pump leading to said economizer topermit said pump to circulate fluid throughsaid economizer and drawn off" through the heat exchanger 50 byfi Said boiler simultaneouslyregulating the extent of opening of the valve in the pipe 51. Heat that is present in this hot water is recovered because some of the 0 feed water passes through the branch pipe 52 and coil 53 in the heatexchanger to the pipe 55. and thence into the furnace wall a" tubes. The portion of the feed water that is thus heated is by-passed around the economizer-so that heat is recovered from the blowoff water without loss of efiiciency.

Some of the feed water will pass through the heat exchanger 50 because the' pressure in the pipes 36 and 37 is greater than that in the mp0 because of the frictional resistance of the econom zer and its connections between the pipe 37 and the separator 25. The read' ings of the thermometers 57, 58 and 59 indicate the temperatures at the respective points so as to guide the operator. The thermostatic control 54 regulates the amount of water that passes through the coil 53 so that when the .temperatureof the water leaving 50 the coil 53 increases an increased amount of water will be permitted to pass through and when the temperature decreases, a decreased amount of water will be permitted to pass through. The thermostatcontrol 54 may,

55 for example, be like that shown in Fig. 1 of Patent #1,543,727.' The connection 62 is provided so that when theboiler is being started up the valve 63 can be openedand water can be kept circulating through the economizer by meansofthe pump 56 during the starting period. The proportionate amount of water that is circulated between the economizer and the boiler tubes can be regulated by" the extent of opening of the valves 63 and 64during the starting period.

4.- The combination with a forced circulation boiler of a pump for maintaining circu: lation therethrough, asteam and water separator connected to said boiler, an economizer connected to said separator, means for feeding water to said economizer, a connection for delivering part of the feedwater to said pump, a blow-off connection for removing Water from said separator, means for heating the feed water delivered tosaid pump by the blow-off water and a separate connection between said'pump. discharge and said economixer to permit said pump to circulate fluid through said economizer and through said boiler simultaneously.

5. In a boiler, steam generating tubes,

economizer tubes connected to said boiler for when starting up.

6. In a boiler, steam generating tubes, economizer tubesconnected to said boiler for feeding water'thereto, a pump connected to the inlet and outlet ends of the generating tubes for circulating water thereto and a.

"alved connection from the outlet side of the pump 'to the inlet side of the economizer tubes for positively circulating water in parallel through said generator and economizer tubes when startmg up.

DAVID is. JACOBUS. 

